code: def y_dist(y_s, y_t):
      dy = y_t - y_s
      return dy
  
file_path: deepgraph/doc/source/tutorials/10min_to_deepgraph.py
imports: import matplotlib.pyplot
  import numpy
  import pandas
  import deepgraph
label_desc: Use image node_id 3 for calling a global function with example usage: y_dist(y_s, y_t) and returns: dy